Hole spin relaxation in [001] strained asymmetric Si/SiGe and Ge/SiGe quantum wells

Details Hole spin relaxation in [001] strained asymmetric Si/SiGe and Ge/SiGe quantum wells Hole spin relaxation in [001] strained asymmetric Si/SiGe and Ge/SiGe quantum wells

2009-06-16

arxiv.org/abs/0906.2865v2

Phys. Rev. B 80, 155311 (2009)

Physics

Condensed Matter

Materials Science

12 pages, 11 figures, PRB in press

Scientific paper

10.1103/PhysRevB.80.155311

Hole spin relaxation in [001] strained asymmetric Si/Si$_{0.7}$Ge$_{0.3}$ (Ge/Si$_{0.3}$Ge$_{0.7}$) quantum wells is investigated in the situation with only the lowest hole subband being relevant. The effective Hamiltonian of the lowest hole subband is obtained by the subband L\"owdin perturbation method in the framework of the six-band Luttinger ${\bf k}\cdot{\bf p}$ model, with sufficient basis functions included. The lowest hole subband in Si/SiGe quantum wells is light-hole like with the Rashba spin-orbit coupling term depending on momentum both linearly and cubically, while that in Ge/SiGe quantum wells is a heavy hole state with the Rashba spin-orbit coupling term depending on momentum only cubically. The hole spin relaxation is investigated by means of the fully microscopic kinetic spin Bloch equation approach, with all the relevant scatterings considered. It is found that the hole-phonon scattering is very weak, which makes the hole-hole Coulomb scattering become very important. The hole system in Si/SiGe quantum wells is generally in the strong scattering limit, while that in Ge/SiGe quantum wells can be in either the strong or the weak scattering limit. The Coulomb scattering leads to a peak in both the temperature and hole density dependences of spin relaxation time in Si/SiGe quantum wells, located around the crossover between the degenerate and nondegenerate regimes. Nevertheless, the Coulomb scattering leads to not only a peak but also a valley in the temperature dependence of spin relaxation time in Ge/SiGe quantum wells.... (The remaining is omitted due to the limit of space).

Affiliated with

Also associated with

No associations

Rating

Hole spin relaxation in [001] strained asymmetric Si/SiGe and Ge/SiGe quantum wells does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Hole spin relaxation in [001] strained asymmetric Si/SiGe and Ge/SiGe quantum wells, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Hole spin relaxation in [001] strained asymmetric Si/SiGe and Ge/SiGe quantum wells will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-475481